The matrix equation XA=ATX and an associated algorithm for solving the inertia and stability problems☆

Abstract We develop a constructive procedure for generating nonsingular solutions of the matrix equation XA = A T X and establish an interesting relationship between a given solution X of the above equation and the associated matrix polynomial p ( A ). The latter is then used to develop an algorithm for computing the inertia of a matrix. The algorithm is more efficient than the other common procedures.